OK, this is pretty cut and dry. You can buy lots of cute little outfits for your baby, but if you want to make your life easier just plan on them wearing little PJs for about the first six months of life. Of course you will spruce them up in outfits now and then, but the standard will be the one piece zip up. No snaps. Trust me. Your baby will be comfortable, changes will be quick and easy and you do not have to worry about coordinating. Bing. Bang. Boom.
I get most of my onesies at Walmart (where the George brand sells 3 for $12.00) or Target (where Carter's one piece zipups for newborns go on sale for $6.00 a few times a year), or the actual Carter's store (only when they are on sale).
Simplify. Trust me.